Yumeko Jabami (蛇喰 夢子 Jabami Yumeko) is the main protagonist of Kakegurui - Compulsive Gambler. She's a transfer student at Hyakkaou Private Academy and the classmate of Ryota Suzui and Mary Saotome. Yumeko’s family is aligned with the family of Kirari Momobami that challenges her for Hyakkaou Private Academy.
Yumeko is a very attractive girl with waist-length black hair styled in a hime-cut, and Burgundy eyes (her eyes become a bright red whenever she is “excited”). She also has pink glossed lips and a hourglass figure.
She wears a red jacket with black trim along the cuffs and collar, a white button-up dress shirt, a dark pleated skirt, a tie, and black/grey stockings, as well as the academy's provided footwear, brown shoes with black soles. She also has simple fingernails, a ring around her left thumb, and a pink/peach colored lip balm.
Yumeko is shown to be a very upbeat and charismatic character who consistently attracts the affection or interest of people around her, usually making a big scene. Not only is she able to befriend those who previously disliked her, she is able to catch the attention of the entire student body. She does just that on her very first day of school and manages to continue doing so on nearly a daily basis. Every time she notices an opponent cheating in games, her button gets switched to a bloodthirsty side of her, usually seen when her eyes turn red and she frightens her opponents.
Though she is typically very friendly, she abstains from acting this way when she uses her perceptiveness to expose her classmates' cheating. She is capable of doing this even after only a couple of rounds of gambling, as she is easily able to decipher what strategies and tricks they are using to skew the game in their favor. While doing this, she may unabashedly condemn the other player and their ways, preferring honesty over politeness in such cases.
Despite the disadvantage she faces when others cheat, she does not concede. This is largely due to the fact that she does not seem to experience fear or anxiety from taking risks. In fact, it gives her a thrill. Because of this, she tends to take high-risk bets in gambles, even if she has nothing to rely on but luck. Though this can sometimes end in her loss, she is emotionally unaffected by the results; she simply uses her loss or gains a means to further indulge her gambling habit. She also wants to make her friends feel the same rush as she does. So while her pushing them into risky gambles might seem irresponsible, she actually means it well.
She seems to be fairly aware of her eccentricities and that her way of gambling doesn't follow normal conduct. As such she rejoices when people support her or encourage her, especially those close to her, greatly valuing their friendship, albeit in her own ways. Despite the obvious joy and pleasure gambling gives her, Yumeko rationally understands that her behavior is immoral and depraved; having admitted that she feels absolutely no remorse or sympathy for the people she has defeated and ruined in a gamble. However despite her lack of remorse of destroying others to feed her gambling addiction, Yumeko has admitted that she instead feels guilty for her inability to sympathize with her victims.
As seen during her first gambles, Yumeko has shown to possess above average and near superhuman levels of senses, memory and observation that only increases her gambling abilities combined with her intelligence. Having been able to easily detect the tiny details within modified cards after only a few glances and apparently tell the difference of a six shooter gun was loaded or not by feeling the small gram weight difference between a unloaded gun and a loaded one.
Kakegurui - Compulsive Gambler
Yumeko transfers to Hyakkaou Private Academy and is shown around the school by her classmate named Ryota Suzui. Ryota tells her about the school which she seems to be interested in. She became popular in her class as she is surrounded by her fellow male classmates. She is then challenged by Mary Saotome to a gambling match which she accepts. She is shown to be losing after after betting one million yen during the first two rounds.
Yumeko then asks Mary for another round to which Mary agrees, when asked how much she's willing to bet, Yumeko reaches into her school bag and produces stacks of yen that amount to ¥10 million. Yumeko then points out that Mary rigged the game in her favor by having 21 out of 30 students place rigged cards that would tip the game in her favor. Yumeko reveals that she noticed these patterns from the beginning and reveals Mary's strategy to her.
Yumeko, of proudness and thrill, wins the gambling match leaving Mary with a debt of ¥8.8 million which she tells Mary that her debt is already paid as their gambling match proved to be a fun ordeal. After that, Yumeko leaves her classroom where Ryota calls out to her. He asks her how she knew about Mary's rigging of the match to which she reveals to him how she deduced everything. She later gives him money to pay his debt that he has to Mary as thanks.
The next day it is seen that Yumeko and Ryota are now friends. They enter their classroom to find Mary's desk vandalized with the entire class smiling menacingly. Mary blames it on Yumeko because of her loss yesterday before lurking away to earn the money back. Ryota takes Yumeko to the cafeteria where he explains the oppressive structure of the school, the student council, and their gambling prowess, increasing her already growing love and excitement towards the school. Yumeko is then invited to play Double Concentration against Itsuki Sumeragi. Yumeko plays a close game but loses the ¥20 million given as a trial.
Yumeko demands a rematch and Itsuki accepts under the condition that should Yumeko lose, Itsuki can remove her fingernails and toenails to add to her nail collection. Yumeko realizes her opponent was cheating and wins on the very first turn by remembering every card's patterns on the back. While Itsuki is in shock, Yumeko confronts her on the cheating and starts spewing out her excitement mixed with anger asking for another game where they both bet their nails. The confrontation caused Itsuki to cry and decline Yumeko's desire making the latter disappointed.
She then is curious in the other Council members and heads to the Traditional Culture Research Club to face off against Yuriko Nishinotouin. There she sees Mary lose against her, making her debt even bigger. Yumeko then gambles against Yuriko and quickly bets a lot of money. She catches on to how she cheats and also points out what a terrible person she is. Yumeko actively makes fun of her and after exposing Yuriko’s cheat, pushed her into betting so much money that it became a great risk for both of them. Kirari Momobami even enters the scene and wants to watch. But due to Yuriko's luck, Yumeko loses and becomes a housepet. After the game, Yumeko checks under the floor and thinks Kirari might have used a small hole beneath the swords to guarantee Yuriko's win.
The thought excites her and makes her want to gamble with the president. The next day, some girls make fun of her for becoming a housepet and call her mittens. But Yumeko then starts to act like a cat and purrs, which freaks the others out. She doesn't mind being a housepet, especially since she has the rights for an official match.
The next day, Yumeko is approached by Jun Kiwatari and his friends, where they command her to strip for them, but she refuses since they're far from her type. Jun gets angry and wants to get violent, but Midari Ikishima steps in and scares him away. Yumeko thanks her and Ryota is also relieved. Soon after the student council holds a special game for housepets, where they can reduce their debt. Yumeko shows up there and meets Mary. Yumeko is in the same group as Mary, which makes her happy, but Mary is still angry at her. They also play against Jun and Nanami Tsubomi.
Yumeko and Mary then decide to come up with a plan to trick him. They wrote down a false debt and switched their boards when no one was looking. During the Indian poker game, Yumeko also noticed how Nanami and Jun were cheating. But, she told Sayaka Igarashi, the dealer, that she wanted to continue playing, without reporting the cheat. Yumeko also tries to convince Nanami to stand up to Jun and tells her that she has to defend herself. In the end she and Mary reveal their twist and they won. Jun is furious and tries to attack Yumeko and Mary for calling him stupid, but Sayaka electrocutes him down. They meet up with Ryota and Yumeko hugs Mary and wants to be friends with her. She acts somewhat clingy, which makes Mary uncomfortable.
The next day, the Student Council was told by Sayaka, that Yumeko actually has a sister. She is apparently hospitalized and Yumeko is paying all of the costs, meaning she must be incredibly wealthy. Yumeko was then planning to challenge Kirari to an official match and asks Ryota to accompany her. But on their way Midari shows up and arrests them. They are escorted to the basement where Midari wants to play a dangerous game against her. Midari confronts Yumeko about being a gambling pervert just like her, which embarrasses Yumeko. Ryota is against it, but Yumeko agrees and trusts Ryota to act as the dealer during the game. She comforts him, by saying they can use "it" as a sign to win. Yumeko already realized that Midari was going to purposefully lose so that she will get shot by her.
During the game in the first round, she loads lipstick into her gun. After she loses, Midari doesn't get to shoot at her, because of that fact. In the second round, Yumeko gets all five of the cards right, since she had memorized all card positions and figured what Ryota would line up. She takes out a gun, but shoots without hesitation. She put no bullets in her gun, making a considerable weight difference. In the third round Yumeko purposefully loses and gets all cards wrong and exposes the fact, that Midari only wants to lose and get shot herself.
She states how much she hates people who gamble only for a selfish gain. She leaves with Ryota with Midari behind them as she cries. After that they do a coin flip for who must pay at a café. She also thanks Ryota for making the gamble interesting. She loses the coin flip, which makes Ryota happy and she laughs.
When she meets Ryota watching a video, she learns about the idol Yumemi Yumemite, who is also a Student Council member. Soon after she is challenged to a game by her. In the cantina, they are approached by Itsuki, who apologizes to Yumeko and asks for her help. Yumeko has no qualms and is very forgiving. They meet up in Yumemi's dressing room. Yumemi acts very sweet and cute but Yumeko sees through her façade; the reason for this being that she had found a threatening letter addressed to Yumemi earlier in a trash can. Yumeko's accusation makes Yumemi angry and she starts to show her true personality. Yumeko then reveals that she has planted a recording device on Yumemi's manager. She says that if she wins their gamble, she will publish that recording in hopes that will make the game more exciting for both of them.
When the live on-stage gamble starts, both Yumeko and Yumemi have to sing something. Everyone finds Yumeko's outfit very cute and she says she's somewhat nervous to perform. Performances are Yumemi's specialty, and although Yumeko sings well, she shouldn't have won. She did win though, because Yumemi meant for it to happen. Yumeko quickly sees through her trick, but plays along without mention of it. She realizes exactly when Yumemi plans to win and when to lose. After the break in the performance, Yumeko changes back into her school uniform after stating she feels most comfortable that way. She then confronted Yumemi about her scheming and stated how they should both be risking something.
When the contest came down to guessing the birthday of an audience member, the dice landed on Mary Saotome leading Yumemi to think that Yumeko can even manipulate dice. However, Yumeko didn't know Mary's birthday and simply guessed June. She purposefully made Yumemi think it could also be September. But she was closer than Yumemi and thus won the entire game. Yumemi was angry but accepted that Yumeko would play the recording. But her fans still didn't give up on her and cheered Yumemi on.
Yumeko then announces however that she found a letter, that seemingly tried to sabotage Yumemi's career, which she cannot forgive and the accused is Kaede Manyuda. He comes down to the stage in order to settle the uproar. Yumeko then wanted to gamble with him. Since he refused, she took off her housepet badge and declared it an official match, which he can't refuse. Then Kaede had no choice but to accept.
At first, they think that they can't even play without a dealer, but the vice-president steps in and says she will act as such. They play Choice Poker. Yumeko bets a lot of money and gets very thrilled throughout the game. However she loses a lot and can't compete with Kaede's bets anymore. Eventually, she asks Itsuki to help her, since she states she's running out of money. Itsuki comes down and helps her out but the bets go higher and higher. Yumeko prompts Itsuki to bet her life (which is a sum of money determined by an individual's worth) and gets gambling crazy. Itsuki becomes determined and takes the risk.
Kaede wants to intervene since such a high sum isn't fair. But then the vice-president takes off her mask to reveal its actually Kirari. Everyone is shocked. Kirari then allows them to continue the game. Kaede is also forced to bet his own life's worth. Yumeko and Itsuki actually planned this together in order for that outcome. In the end, Yumeko wins and Kaede is devastated. While his unconscious body is transported away, Kirari talks with Yumeko. They find out how much they agree about things and they want to play a game together. And both of them plan to bet everything they have.
The next day, Ryota confronts Yumeko wondering if she's really prepared to go up against Kirari without knowing what she may do. Yumeko is grateful over the fact that he's worried about her but that there was no need to since she can't hold herself back on facing a challenge like Kirari. Fully aware he couldn't convince her otherwise, Ryota calms himself down and states that he isn't there to stop her and that he wants the chance to see her gamble from the best seat in the house leaving her surprised to hear him say that. This also makes Ryota realize that he's fallen for Yumeko. Mary and Itsuki step in giving her loaded dice and X-Ray cards, but Ryota and Yumeko stop them because Yumeko has no intention of cheating. Unable to convince her otherwise, they decide that the only thing they can do is support Yumeko, and Yumeko thanks all three of them for their support.
The game Kirari chose is called Tarot Cards of Fate. Three people will draw a card, which is them and Ryota. He doesn't want to take so much responsibility, but Yumeko is excited because she wants him to be part of this gamble. The stakes for the game are that whoever loses will have to leave the school. That means Yumeko wouldn't be able to gamble anymore which would mean she lost everything. She then draws the first card. It is The Magician, the second card in the Major Arcana, which is marked 1. While Kirari decides, she talks to Yumeko about the existence of fate. Yumeko is very intrigued by that.
When Kirari draws The World, the largest number in the Major Arcana, she gets a -21, and Yumeko doesn't really react. Since Ryota now has to draw a card, he is extremely nervous. Yumeko tries to calm him down, by saying only she can lose, but he refutes her statement by reminding her that he wanted to watch her from the best seat in the house.
He confesses his feelings for her when he states that he wants to be with her and that the risk she's trying to carry by herself is just as much his leaving her flustered. He notices a mark on one of the cards, which could be the instant win card. The others tell him to take it, but he is unable to take that risk. So he announces that he wants to draw a random card of his own free will. Hearing that from "her Ryota", Yumeko immediately gets her very excited. She clings to his back, takes his hand and tells him to take the ultimate risk. So he draws one and its +20. The total score is 0, which means the game ended in a tie. Yumeko looks forward to playing again with Kirari and states, that since fate wanted both of them to stay, life must have something very exciting in store for them. When Kirari calls Ryota and Mary subjects, Yumeko denies that and states that she has found the best possible friends that she could ask for.
Yumeko is very excited about the election and all the gambling she can do. She is a bit disappointed that she can't gamble with money after she won so much from Kaede Manyuda. She is also intrigued by the thought that distant relatives of her have arrived at the school. When Mary Saotome comes, Yumeko runs towards her excitedly, only to be stopped by Mary. She reminds Yumeko that the arrivers might be after her, and Yumeko believes they could be distant relatives of hers. But Yumeko is happy as long as she gets to gamble. They are called by Rei Batsubami and she tells them that they have been invited to a game that Erimi Mushibami prepared involving a guillotine. Yumeko is very thrilled about this and can't wait to try it out. She asks Ryota Suzui to try it too, but he declines. But she will have to play with Midari Ikishima, who she still dislikes, which she also clearly shows.
During the game, she does not hesitate and shows no fear when cutting the threads. Before the game she noticed that the table was missing a stopper, which made it shake, so she asked the observer to remove them. When she again asked Inaho during the game, if she had removed them, Erimi thought that she meant the plate protecting their fingers from actually being cut off. Erimi began to hesitate and became nervous. Yumeko hurried her, until she started to cry. Yumeko and Midari were taken aback by this, but then they both shouted at her to continue. When it came down to only two strings, Midari cut them both at once.
Erimi pulled out her finger and so Yumeko won. She explained how a chance between two string was like a gamble from heaven, but Midari took it away. She was extremely angry at Midari for taking away that 50/50 chance in the end and told her to leave. She then thanks Erimi for the great game and said she wanted her to feel the same fear as they did.
The next day, they are again invited to a gamble this time byMiyo Inbami and Miri Yobami. When they meet, Miyo hugs her and they both say how nice it is to finally meet. Runa is also overseeing the game, since she doesn't trust the Momobami sisters. They are playing Nim Type Zero. Ryota notices the huge disadvantage against Yumeko, so he tells Runa that he's partaking not only in this game but also in the election as well. Miyo and Miri agree to his inclusion, Yumeko clings to his arm admitting how happy she that they get to gamble together again. She enjoys the game, but halfway through she starts feeling sick. She has to lay down on a couch. It turns out that Miyo poisoned Yumeko while hugging her. Under the effect of that poison, she starts to lose conscience. Mary steps in to take her place and Yumeko then quickly tells Ryota to trust in Mary. They manage to win and then bring and treat Yumeko to a hospital, along with Rei's help.
When Yumemi Yumemite wants to get more votes, she approaches Yumeko and wants to gamble with her. But, an unexpected guest named Kawaru Natari, who is secretly one of the Momobamis as her real identity is Sumika Warakubami, steps in and in turn challenges them to a game. Yumeko didn't know who she was, much to the others disbelief as Kawaru is a famous actress. Yumemi states she wants to do anything to win, since she's sure Kawaru will cheat as well. Yumeko is for once fine with cheating and excited, since if both players cheat it's even again. Yumeko and Yumemi sing together on stage. When they still lose the first round, Yumeko is excited and asks Yumemi what they should do now.
Yumemi is annoyed because she is surrounded by weirdos. In the second round, both Yumemite and Natari must taste a spicy macaroon. Kawaru correctly guesses which one of the three was Yumemi's spicy one. Yumeko counted how often Kawaru chewed with each macaroon and was able to eliminate A since she chewed the most there. And then she randomly picked B, which was correct.
While Runa Yomozuki was preparing the third round, Yumemi talked about how she felt inspired after she realized she could never beat Kawaru. She stated, that she now wanted to be defeated by her greatest idol. But Yumeko didn't like that Yumemi was going to have fun without her. She dislikes people who give up so easily and told her how pathetic and cowardly her behavior is. So in the third round, she didn't cooperate with Yumemi at all and always truthfully said which card she drew. This allowed Kawaru to easily read both of them. Yumeko said, that she was done with Yumemi.
Yumeko was certain that the total has passed 63 but wanted to keep the thrill going. But after some motivation from her fans, Yumemi got some faith back. Yumemi asked Yumeko to pass now and they would surely win. Yumeko believed she was acting the whole time and was incredibly impressed, but Yumemi quickly told her that her struggle was real and that she can't act at all. But Yumeko was still content with her gaining back faith and went along with Yumemi, which resulted in Kawaru's loss and their win.
After that game, Yumeko quickly contacted Terano Totobami and wanted to play the Greater Good Game. She chose Itsuki Sumeragi and Kaede Manyuda as players, while Terano chose Ibara Obami and Miroslava Honebami. She is excited to play the game, but didn't want to work together with Ibara to take down Kirari. Rumia Uru explains the rules and the first people go to spend their coins. While that happens, Kaede asks Yumeko whether she ever feels any remorse when destroying an opponent. She replies, that she only feels remorse for not feeling remorse. Rei gets extremely angered by her coldness and mentions her hospitalized sister. Yumeko simply replies by asking her if she ever saw anyone fall into despair, to which she retreats. When Itsuki returns, Yumeko excitedly asks her if it was fun.
After the results of the first round are announced, they realize there must be a traitor. As the discussion becomes more heated, Yumeko is sure something exciting will happen. She then has the idea to write down a number for each player and that amount they must pay. That way they can estimate how many traitors there are and maybe even who.
But there still seemed to be two traitors. Kaede then pointed the finger at Yumeko. She didn't deny it and during the next round, she was excited about how no one trusted her at all. She thought it unfair not to share the thrill and went up to him, telling him that they should do it together. Then they both reveal themselves as the traitors and that they will pay zero coins in the next round. That was just a trick in order to get the others to pay, which worked out. Yumeko was glad that not everyone lost. At the end of the next round, Kaede then figured out that the true traitors are Miroslava and Itsuki. Everyone agreed to expel Miroslava and the game was then over. Yumeko managed to win 16 votes. When Itsuki's bet with Terano was revealed, Yumeko declared it simple self-perception. But she knew it was for the best and admired Itsuki's decision, stating that, "choosing how you die, is choosing how you live". Then, Itsuki officially retires from the election.
The next day there was a broadcast going on. During the broadcast, Yumeko challenged Kirari to a game in front of a live camera. She states that she would be ready to even gamble right now. But, Sayaka Igarashi rushed in and calls Yumeko a pestilence to the school and wanted to bet everything with her. Kirari saw that opportunity and brought them to the Tower of Doors. She explains to them, how they must travel through the tower. Yumeko is fascinated by the building and is amazed how it was constructed for gambling alone. During the first round, Yumeko distracts Sayaka from seeing her answer, which triggers her. Yumeko then opened the middle door, but the staircase was gone. While Sayaka climbs down, Yumeko opens one of the outer doors.
She told Kirari she wants to know all the mysteries of the tower and would rather die knowing it all. Since the moon wasn't visible from the door that it should be, she deduced that the entire tower was rotating with them. She arrived at the bottom later than Sayaka. She laughed at Yumeko for being so oblivious. Yumeko cheered Sayaka on and went on her way.
But since she didn't know the Tower's secret, Yumeko was able to use the middle stairs and get all the way up, though quite exhausted. Yumeko congratulates Sayaka on getting up so quickly. Sayaka didn't understand, how Yumeko was faster than her. Yumeko explains the rotation of the tower and Kirari is pleased that she likes the building. She won the game because she acted through curiosity and not simply through logic, something Sayaka could have never done. Sayaka confesses her love for Kirari and jumps out. Kirari follows and they both land on a mattress. Yumeko watched and was very satisfied with the gamble. She thought about how one's feelings for someone else can never be outlawed and how these two opposites apparently really do attract each other.
When she and Ryota enter class, they find envelopes with invites to an auction. Yumeko attends of course and is excited. When going there, they meet Midari and Yuriko. Midari wants Ryota's help for getting Yumeko's attention back. But Yumeko coldly ignores her and asks Ryota why he talks to himself. She keeps acting as if she can't see Midari at all. Rei then greets them all and the auction begins. Yumeko is also glad to see Inaho again and hopes for a good game. At first, Mary thinks Yumeko made a stupid bet, but she denies she did it. She still encourages everyone to bet, since it wouldn't be fun otherwise.
When Mary gets annoyed at Midari, Yumeko again questions her, why she's shouting at thin air. Yumeko also talks to Inaho and requests that the money she won from Kaede is brought in. Mary comes to the conclusion that Rei is also secretly participating. She promises to stop, but through some bets they also deduced that there must be more players in another room. The election observers then bring in the 3 million Yen. Yumeko challenges Rei and wants to gamble with the real her. Rei agrees and drops her façade.
She tells everyone about her revenge plan, but Yumeko wants to continue the auction. Everyone is stressed out since Rei is the only one profiting. But then Yumeko starts to instantly bet 101 votes. She continues to do that and gains nothing from it. No one dares to bid anything since it would be worthless. Soon the others catch on, that she was trying to send them a message. They all bet really low amounts and no one else intervenes. That way everyone won a lot and Rei is losing. After she has no votes left, Yumeko reminds her that she still has all the money she gave her.
She states how she finds gambling fun, how she loves the moment when you risk everything. Rei realizes how crazy Yumeko is. When she was a child and peeked into the hospital room of Yumeko's sister, Yumeko was also there but didn't seem to worry about her sister but only interested in gambling. Yumeko pushes Rei into betting something for her sake alone and then she would be able to enjoy gambling. Rei accepts the gamble and wants to break the invisible chains of the Batsubami name. Yumeko stakes her family name and Ririka Momobami comes on stage and suggests a coin flip, to which they agree as she flips the coin. Yumeko won and got the 3 million Yen back.
But, Kirari was so impressed by Rei that Kirari took Rei back into the clan. Yumeko then went on to gamble with everyone that wanted to and lost all of the votes she won from the auction. She didn't mind however and was simply enjoying herself. She then sees Rei pass by in the hallway and Yumeko is happy for her as Rei became her own person.
After the War game, she bumps into Mary and Ririka. At first, she does not recognize Ririka without her mask. Later she meets Nanami in the bathroom, being harassed by two bullies. She suggests that they gamble with her and bet everything, which makes them run away. Yumeko then approaches Nanami to gamble with her and proposes betting all that she has. Yumeko again tells her, that she will never get out of her situation if she doesn't take any risks. Nanami is scared but accepts.
Soon after, Yumeko is invited to the great tournament. She is excited to participate in such a big gamble. She talks to Mary outside and hopes it will be fun, although they are rivals. She also keeps cheering Mary on, despite that fact. During the Rock Paper Scissors Poker, she wins against Erimi. After discarding her first hand, she bets everything and wins, due to having five scissors. Erimi then accuses her, of simply making fun of her, by going all-in and teasing her. Yumeko explains, however, that she simply had to strategize and that the single matches, have to be seen as part of the big picture.
Yumeko's personality was portrayed quite faithfully. While the sexual elements in her behavior were toned down, she maintains the same excitement as her counterparts from other media. When she's extremely thrilled, her eyes become red like in the anime.
Kakegurui - Compulsive Gambler
- A Girl named Yumeko Jabami
- Boring Girl
- The Slit-Eyed Girl
- The Girl Who Became a Pet
- The Girl Who Became Human
- Tempting Girl
- Refusing Girl
- Love-Dancing Girl
- Dreaming Girl
- Selecting Girl
- The Girl Who Bets Her Life
- The Girl Who Gambles Compulsively
- Gambling Girls Again
- The Girls of the Momobami Clan
- Do Not Touch this Girl
- Communicating Girls
- The Girl who Changes
- The Hollywood Star
- The Treacherous Girl
- The Winning Girl
- The Girl by her Side
- The Logical Girl
- The Girl who Bears the X
- The Null Girl
After losing to Yumeko in Vote Rock, Paper, Scissors, she became very angry and bitter, but Yumeko did not hold a grudge against her. In the Debt Swapping game, they allied and became friends, participating in numerous bets since then and attempting to defeat the Student Council.
Regardless, they are friends and can work together if necessary.
He showed Yumeko around the school when she arrived, and after Vote Rock, Paper Scissors game - where he helped Mary by cheating - Yumeko thanked him for making the game so fun and interesting. Ryota continued to teach him school and, little by little, a friendship grew between them.
At first, it would appear both were enemies since Yumeko had defeated Itsuki, however, in the interests of Itsuki herself, she began to become close to Yumeko, with the possibility that she might win a position on the Student Council if Yumeko were to take over the position of President. They have trust in one another and can be considered friends.
Midari begged Yumeko for a bet, and with her, played the ESP game. After Yumeko saw what Midari intended with the game, losing without giving the opponent a chance of victory, Yumeko made it clear to Midari that she despised her.
- The name Yumeko means "dream, vision," (夢) (yume) and "child," (子) (ko).
- Yumeko's surname Jabami means "snake, serpent," (蛇) (ja) and "bite, eat, drink, receive (a blow), (kokuji)" (喰) (bami).
- It can also mean "hard drinker."
- In the first volume, it was revealed that Yumeko lives alone because her parents have passed away from unknown causes and she has an older sister, who is currently being hospitalized.
- It was also revealed that despite having no other relatives and not working, Yumeko was stated to be incredibly independently wealthy. As seen where she manages to easily pay for her sister's hospitalization and private treatment in a specialized university ward for a prolonged period of time. Hinting that Yumeko had either possessed a large inheritance from her parents or acquired her wealth somewhere else.
- Yumeko and Therse Alexanderite from Tate no Yūsha no Nariagari (The Rising of the Shield Hero) have the same voice actresses in Japanese and English.
- When climbing the stairs in the Tower of Doors, Yumeko mentions that she has very little stamina.
- "Let's get our gambling freak on!!" - To Multiple
- "Show me what it means to risk!!" (English Dub) - To [Ryota Suzui]
- "Gambling is fun because both people feel pain at the same time. So why did you try to make it so that you alone felt the pain in this game? You do not enjoy gambling. You simply wish to die. You're the type of person I hate the most. To speak frankly... you piss me off." - To Midari Ikishima
- "Gambling is my life’s purpose. I don’t need anything else." - To Rei Batsubami
- "Instead of living on in ignorance, wouldn’t you rather die, knowing everything?"
- "Choosing the way in which you die is also choosing the way in which you live."
- "I despise people who move the goalposts because they think they can’t win."
- "Isn't that what makes it all fun? Madness is the essence of gambling, isn't it? In capitalist society, money and life are the same thing. And no person with his right mind would trust his own life to Hands of fate. Even so, people still crowd the casinos because they enjoy the madness of betting their own lives! In that case, the crazier the more betting is enjoyed! Let's get on with our game!" -To Mary Saotome
- " I don't like situations where I know I'm going to win or I'm going to end up losing. And that doesn't happen in games of chance. Today I took part in an exciting bet thanks to you, Suzui. Thank you very much indeed." - To Ryota Suzui
- "This time, why don't we both bet our nails? And whoever loses will have to take all their fingernails and toenails off too! "They say it's very agonizing after your nails are pulled out and it always bleeds when you put pressure on your fingers. And since we're talking about all the nails, I know it's going to hurt our daily lives. Making a bet like that and with so much at stake... Just thinking about it... I get all excited!" -To Itsuki Sumeragi
- "Is that I'll have to refuse I will not let strangers see me naked and the truth is that the three of you... You three do not make one bit my type." -To Jun Kiwatari and his friends
- "Tsubomi, you don't mind leaving him abuse you? Are you telling yourself you're going to have to put up with this kind of abusive treatment until you graduate? Know that your thinking is wrong. If the person doesn't have the will to fight some injustice within him, he will stay the same way. You will spend the rest of your life like an animal. Do you want to spend the rest of your life with your head down? Maybe you have to obey school rules in general, but now you have a fighting chance and if you don't take that chance, you'll look just like a pig that refuses to come out of a cage with the door open. You'd be proving to everyone that you're just a pet. Oh, or is this how you want to live? You're really scared of fighting, so you better suck up to him and maybe he'll be just a little nicer to you. I get it, yeah, after all, this can be a way of life, but it's a way I honestly don't understand. So, you really should give Kiwatari to win. Maybe it's better that way, don't you think? It is not? Tsubomi, the eternal pet." -To Nanami Tsubomi
- "Kiwatari, it's always a mistake to judge things based on their own parameters. After all, people think differently. There are forgivable and unforgivable things, and the truth is, no one will ever obey you one hundred percent. And that's good, isn't it?" -To Jun Kiwatari